Global Patent Index - EP 0740822 A1

EP 0740822 A1 19961106 - METAL DETECTION SYSTEM

Title (en)

METAL DETECTION SYSTEM

Title (de)

METALLDETEKTORSYSTEM

Title (fr)

SYSTEME DE DETECTION DE METAUX

Publication

EP 0740822 A1 19961106 (EN)

Application

EP 95910863 A 19950119

Priority

  • US 9500380 W 19950119
  • US 18369694 A 19940119

Abstract (en)

[origin: US5680103A] A walk-through metal detection system with split field generation coils excited in phase to generate an electromagnetic field having a substantially uniform vertical field density. A plurality of vertically distributed receiver coils are also provided, each receiver coil connected to a separate detector circuit for detecting disturbances in the generated field caused by the presence of metal objects. The signals are processed to generate an output signal indicative of the individual metal mass (or masses) of objects detected within the generated electromagnetic field. The output signal is compared to a threshold signal, and if greater than the threshold signal, then a metal object is presumed to be present within the electromagnetic field and an alarm is sounded. A remote control may be used by an operator to adjust the threshold signals. Additional processing of the detector circuit outputs differentiates between a single object of large metal mass and multiple objects of combined metal mass. The detector circuit outputs may be processed to differentiate between ferrous and non-ferrous metal objects and differentiate between the metal compositions of various metal objects.

IPC 1-7

G08B 13/24

IPC 8 full level

G01V 3/10 (2006.01); H03K 17/95 (2006.01)

CPC (source: EP US)

G01V 3/105 (2013.01 - EP US); H03K 17/9525 (2013.01 - EP US)

Designated contracting state (EPC)

AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

US 5680103 A 19971021; AT E244435 T1 20030715; AU 1867195 A 19950808; AU 686341 B2 19980205; CA 2179993 A1 19950727; CA 2179993 C 20041019; DE 69531194 D1 20030807; EP 0740822 A1 19961106; EP 0740822 A4 19990818; EP 0740822 B1 20030702; MX 9602831 A 19980131; US 5521583 A 19960528; WO 9520205 A1 19950727

DOCDB simple family (application)

US 61468796 A 19960313; AT 95910863 T 19950119; AU 1867195 A 19950119; CA 2179993 A 19950119; DE 69531194 T 19950119; EP 95910863 A 19950119; MX 9602831 A 19960718; US 18369694 A 19940119; US 9500380 W 19950119